A recent thread talked about a radio inside a metal box. That reminds me of a question I never resolved. 9 years ago my sailboat was struck by lightning. 6 people were on board, but nobody was hurt, luckily. My mast is grounded to an underwater plate via a thick copper cable inside a plastic conduit. But the EMP fried all my electronics including hand held devices. Since then, I try to protect my devices by putting them in the oven of my stainless steel stove, or in cookie tins. I have no proof of these protections being effective. Lightning has many frequencies. My goal is not perfect shielding, but just enough attenuation of the EMP to let my devices survive. I expect that there is a lot of military research on this topic, but I don't have any references, or any way to compare weapons EMP with lightning EMP strengths. Ovens and cookie tins, effective or old wives tales?